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Epigenetic Inheritance in Plants

Epigenetic inheritance in plants reported ScienceDaily 11 February 2014 and Science DOI: 10.1126/science.1248127 6 February 2014. “Epigenetics” refers to modifications made to genes during an organism’s lifetime, usually involving the addition of chemical tags that influence when the genes are activated or deactivated. These do not change DNA code, and therefore it has been assumed they are not passed on to the next generation. However recent research indicates they can be passed on in plants. Frank Johannes of University of Groningen Bioinformatics Centre explained: “While in mammals epigenetic marks are typically reset every generation, in plants no such dramatic resetting takes place. This opens the door to epigenetic inheritance in plants: epigenetic changes that are acquired in one generation tend to be stably passed on to the next generation”.

Johannes and a group of Dutch and French scientists have now studied a number of strains of Arabidopsis plants that were almost identical genetically, but varied in epigenetic markers. The researchers identified epigenetic markers that resulted in variations in flowering time and root architecture and found these could be inherited in a stable way for seven generations. According to ScienceDaily, “It is the first time that epigenetic differences have been unequivocally shown to contribute to heritable traits”.

Johannes commented: “This is a breakthrough, because it changes the way we view genetics”. However, he also commented that “because epigenetic inheritance differs between plants and mammals, it is by no means certain that similar processes play a role in mammalian populations like humans”. The research team deliberately induced the epigenetic traits they studied in the laboratory, but many of lab-produced epigenetic changes also occur in natural populations “and may thus provide an epigenetic basis for Darwinian evolution independently of DNA sequence changes”.

Editorial Comment: Epigenetic changes certainly contribute to adaptation, i.e. the modification of already existing characteristics to enable a plant or animal to cope with changes in the environment. However, there are limits in epigenetic changes, because they do not alter the DNA therefore they cannot add any new characteristics or change one kind of plant into another. Therefore, they cannot be a basis for evolution. The deliberately modified plants in these experiments have remained the same species, so there is no evolution involved.

Epigenetic changes have long been known to occur in response to environmental stimuli, and definitely function as a built-in mechanism for enabling plants to adapt when they find themselves in a new environment. Because they are now shown to be passed on, it also now means that succeeding generations of plants will already have the variations needed to survive in that environment, and get a good start in life.

These discoveries fit well with Genesis, which tells us God created plants according to their kinds, and to provide food, habitat and a pleasing environment. Thus, their genes enable them reproduce after their kind, and their inbuilt ability to use epigenetic changes gives them the potential to adjust to variations in the environment, without changing ‘Kinds’. These new discoveries about epigenetic changes certainly seem to be part of God’s provision for his creation, given his foreknowledge that the world would go downhill from Creation after man sinned. (Ref. inheritance, botany, adaptation)